The present invention relates to an apparatus for collecting and isolating a fluid specimen, and more particularly to a cup which can be used to receive, transport and store a fluid specimen as well as to provide an isolated sample for a fluid characterization testing.
Many tests are conducted to characterize the component or detect certain components or compounds of interest in fluids from the environment or body fluids. For example, employers sometimes test urine samples of prospective employees to determine whether the individual abuses controlled substances such as illegal drugs. Generally, a fluid sample is collected in an open mouth jar, and then closed and transported to the testing location. Several types of devices have been designed to collect uncontaminated urine such as the devices disclosed in U.S. Pat. Nos. 4,040,791; 4,393,881: 4,557,274; 4,569,090 and 5,797,855.
After a sample is collected, it is important to maintain the integrity of the sample until the time of testing. Adulteration of the collected fluid should be prevented to ensure an accurate test result. To prevent adulteration after collection, the cup contents should be maintained in a securely sealed, uncontaminated state.
In the testing of a fluid sample, most collection cups require opening the collection cup lid and transferring a small amount of the sample for testing. Many fluids being tested such as body fluids are considered to be potentially infectious and should be handled with proper caution. The test operator and/or surroundings can be contaminated and infected during transfer by contact with or spilling the sample fluid. Furthermore, the collected fluid sample itself can be contaminated by the surroundings and thereby lose its integrity. When the sample is transferred and tested, the identity of the sample can be confused with others, resulting in an uncertain conclusion. Therefore, it would be desirable if the test can be performed without transferring the sample fluid from the original collection cup.
U.S. Pat. Nos. 3,980,436; 4,385,115; 4,827,944; 4,960,130; 5,016,644; 5,038,793; 5,077,012; 5,215,102; 5,283,038; 5,368,583 and 5,403,551 disclose the introduction of test strips or other test devices into a specimen collection device in a general sense. These devices permit the testing of a sample without requiring transfer of the sample out of the collection device. However, some of these devices present problems with mechanism for communicating the sample to the test strips or they cannot ensure that at least a portion of the original sample remains isolated from the initial testing, since the test strip or test device is not isolated from the main body of collected fluid and consequently contamination from the test device is not eliminated.
It is highly desirable that the integrity of a fluid sample be maintained for later use of the sample, especially in the case of testing of urine for the presence of drugs. The collected urine sample must generally be kept until a confirmation test is later performed.
U.S. Pat. Nos. 4,976,923; 5,119,830 and 5,591,401 disclose in general terms urine collection cups that have a test strip on the lid. In these devices, it is typically necessary to invert the cup in order for the sample to be contacted with the test strip and spilling of the sample fluid can occur if the lid is not tightly closed. The collection cup in U.S. Pat. No. 5,976,895 can be used to collect and test urine in the same cup. However, the specimen is not divided into two portions prior to testing and contamination of the specimen from, for example, the test strip can occur.
Thus, there is a need for a fluid collection cup that is easy to use and prevents contamination from both laboratory technician and collected fluid by preventing contact of one with the other. Second, there is a need for a fluid collection cup that can be transported without spilling the sample and that is protected from tampering after collection. Third, there is a need for a fluid collection cup that can preserve collected fluid in a secure, intact state until the time of a confirmation test.
These and other features and objects of the invention will be more fully understood from the following detailed description of the preferred embodiments which should be read in light of the accompanying drawings.
This invention is a fluid sample collection and isolation device that has a secure locking system and a sample isolating cylinder that has a tamper evident locking system. The sample isolating cylinder separates a fraction of the fluid, for testing, from the main fluid in the collection cup. Using this fluid collection and isolation device, sample transfer to a separate vessel for testing is not required and the integrity of the collected fluid for further confirmation testing is maintained.
The apparatus for collecting a fluid specimen has a collection chamber with a sidewall and bottom for receiving a fluid specimen. It also has a fluid isolation assembly comprising a cylinder means having an interior sidewall, an upper portion and a lower portion and a piston slidably disposed within the cylinder means and in contacting relationship with the interior sidewall. A passage communicates between the collection chamber and the interior of the cylinder means and the passage is positioned to permit at least a portion of said fluid specimen to enter the lower portion of the cylinder means. A conduit communicates between the lower portion of the cylinder means and a isolation chamber. Preferably, the isolation chamber is formed by the sidewall of the cylinder and the top of the piston. The conduit is disposed to transfer the portion of the fluid specimen from the lower portion of the cylinder means to the isolation chamber when the piston is moved from the upper portion towards the lower portion of the cylinder means. Preferably, a one-way valve is disposed within the conduit to prevent fluid from returning from the isolation chamber into the lower portion of the cylinder means.
In a preferred embodiment, the collection cup has the usual shape of a cup and lid, but an isolation cylinder is attached to the center of the lid. The lid has a locking system that works in conjunction with the base container so that once the lid is closed, it cannot be opened without cutting the tamper evident locking system. In the isolation cylinder, a piston is installed, which functions to isolate the fluid for testing in the upper portion of the isolation cylinder. Once the cylinder tamper evident seal is broken and the cylinder lid is removed, the piston is pressed with a stick test device or other plunger means so that the fluid below the piston is forced up through a conduit in the piston and forms an isolation chamber in the upper portion of the cylinder. The fluid in the isolation chamber is used for testing for specific analytes. The piston is designed with a one-way valve to prevent back flow of the fluid once it goes into the upper portion. Therefore, the fluid in the isolation chamber is isolated completely from the portion of the sample remaining in the collection cup or base container. The fluid in the collection cup remains intact, without any contamination, before, during and after testing.
The top of the isolation cylinder has a cap with a slot, into which the test device is introduced. A typical stick-type test device can be used to press against the piston and move it towards the bottom of the isolation cylinder. Another lid with a locking device may be placed over the isolation cylinder to prevent tampering before testing and replaced after use to prevent spilling of the fluid above the piston in the isolation chamber. To control the fluid volume into the isolation chamber, there is a space below the piston in the lower portion of the isolation cylinder. There is at least one aperture in the isolation cylinder wall positioned above this lower portion to allow fluid from the collection cup to flow into the bottom of the cylinder. Only the volume of fluid that fills the space below the aperture is pumped above the piston. When the piston is moved to the bottom of the isolation cylinder, it also serves to block the opening and prevents fluid from returning to the collection cup.
In a preferred embodiment, the cup has a lid assembly with a tamper evident closure; a cylinder that extends into the fluid in the collection cup, also with a tamper evident closure; a piston with a conduit and one-way valve through which a portion of the fluid can be forced into an isolation chamber separate from the main collection cup for testing. The lid assembly cylinder is configured with an aperture near the bottom of the cylinder to allow a small portion of fluid to enter the lower portion of the cylinder from the collection cup chamber and a piston with a central conduit and valve initially positioned near the top of the cylinder adjacent to the lid. The piston, when pushed down the cylinder, closes the aperture communicating with collection cup chamber and forces a predetermined volume of fluid from the lower portion of the cylinder through the conduit and valve to the upper portion of the cylinder, isolating a portion of the fluid sample from the fluid in the collection cup chamber. The valve prevents the fluid from returning to the lower portion of the cylinder and to the collection cup chamber. A testing device may be inserted into the fluid sample at the upper portion of the piston for characterization of one or more analytes in the fluid sample.